Automatic stop governor



July 28, 1931.

F. A. MEYER AUTOMATIC STOP GOVERNOR Filed Aug. 1, 1928 WITNESS ATTORNEYPatented July 28, 1931 UNITED STATES PATENT OFFICE mean: A. MEYER, orNoawoon, PENNSYLVANIA, AssIsN'oR T WESTINGHOUSE ELEC- rare atmmurscruame COMPANY, A CORPORATION or rnnnsytvanra AUTOMATIC s roreov'aaNoR Application filed August 1, 1928. Serial No. 296,832.

My invention relates to an automatic stop governor for a prime mover,and it has for its object to provide apparatus of the characterdesignated which shall be simple, and alsoreliable in operation.

Another object is to provide an automatic overspeed stop governor whichmay be set without stopping the,prime mover, and a further object is toprovide means for testing such a governor at a speed less than theoverspeed for which it is set, without first shuttin down the primemover.

nother object of the invention is to provide an automatic overspeed stopgovernor of the hydraulic or fluid pressure type.

Afurther object is to provide an automatic stop governor which shutsolithe supply of motive fluid upon failure or predetermined diminution ofthe fluid pressure at the inlet of an impeller for a fluid pressuregovernor. In accordance with my invention, I provide an elementsubjected to fluid pressure varymg as a function of the speed of theprime mover and bias said element in op osition to the fluid pressure bya constant orce, such as the force of gravity of a number of weights Theamount of said force is such as to exceed or equal the force of saidfluid pressure until a predetermined overspeed is exceeded, when saidelement is effective to shut oil the supply of motive fluid to the primemover.

The above and other objects are effected by my invention, as will beapparent from the following description and claims taken in connectionwith the accompanying drawing, forming a part of this application, inwhich: I The single figure is a diagrammatic view of my automatic stopgovernor controlling the throttle valve of a prime mover parts thereofeing shown in section. Pteferring now to the drawing in detaiL-I' showmy novel governor applied to a prime of the casing 11 su ortin a theshaft. 'rheshfr i 10 his mounted directly thereon and in an impellerhousing 15. The impeller provides a fluid pressure which varies as thesquare of the speed of the prime mover. The

bearing 12 for an impeller 14:

of a piston a fragment of,

disposed withfluid which is used to provide this pressure is preferablylubricating oil which is also used for lubricating the bearin 12.

Motive fluid for the prime mover, hereinafter referred to as steam, issupplied thereto through a throttle valve 16 and a governor valve 17.The governor valve 17 is controlled and operated by a fluid pressuregovernor 18, having a piston 19 disposed in a cylinder 20.

The piston is operatively connected to the valve 17, and is biased toopen the valve b a spring 20. The piston 19 is also subjected to thepressure developed by the impeller 14, which is transmitted theretothrough a conduit'21, and which acts on the iston in opposition to thespring 20 and to close the valve 17.

Upon increase in speed, the increased oil pressure moves the piston 19to decrease the valve opening 17, and upon a decrease in speed, thedecreased pressure permits the spring 20 to move the piston 19 forincreased valve opening.

It will be apparent that this form of governor for the valve 17 is shownmerely for example, and that any type of speed governor may be used, orthat a governor may be omitted.

At 23 I show a reservoir for supplying oil to the impeller 14. Oil fromthe reservoir 23 flows by gravity to an ejector 24, which is motivatedby oil pressure transmitted throu h a conduit '25 from the impeller 14,and w ich supplies the oil at a lower pressure to the inlet of theimpeller through a conduit 26. The conduit also supplies oil to thebearing 12. I

' The throttlevalve 16 is operated by a throttle valve operatingmechanism 28 consisting 29 connected to the throttle valve, a cyliiider30,11 spring 31, and a screw-thread ed stem 32. A passage 33 is providedin the piston 29 ,for providing communication between the upper andlower ends of the cylinder 30. The upper end of the passage is adaptedto be covered by the lower end of the stem 32. Fluid pressure issupplied through a conduit 34 to the lower end of the cylinder 30 toactuate the piston 29 in valve opening direction, and a drain condiut 35I communicates with the cylinder'30 above the i "so piston 29 andconveys the oil drained thererom to the reservoir 23. A restrictedorifice 27 is interposed in the conduit 34 to limit the flow of fluidtherethrough.

The valve operating mechanism 28 is controlled by my novel automaticstop governor 36, which will nowbe described. This governor includes acasing 37 having a cylindrical bore 38, a second cylindrical. bore 39and a third cylindrical bore 40'. Disposed within the housing 37 is anelement 41, which has a piston 42 in the cylindrical bore 39, a sleeveportion 46 extending therefrom, the end of which fits in the cylindricalbore 40, and piston portions 43, 44 and 45 carried by the sleeve 46 andfitting in the bore 38. The sleeve portion 46 is provided with anannular row of ports 47 above the piston portion 43, a second row ofports 48 between the piston portions 43 and 44, and a third row of ports49 between the piston portions 44 and 45.v Thecasing 37 hasa port 50communicating with the impeller 14 through a conduit 51, and a port 52communicating with the conduit 34. The casing 37 is also provided withports 54 and 55 communicating with the drain conduit 35.

Extending through theupp'er end of the a casing 37 is a stem 56, on theupper end of which isformed a disc 57 adapted to carry a plurality ofweights 58.

Disposed within the sleeve portion 46 is a valve member 59, havingpiston portions '60, 61 and 62. The lower end of the valve member 59 issecured to a piston 63 which is biased downwardly by a compressionspring 64.

The piston 63 is biased upwardly, however, by the pressure of the fluidsupplied to the impeller 14 through the conduit 26, which pressure isconveyed to .the lower end of the casing 37 through a conduit 64'.

A chamber '65 is formed between the piston portion 45 and a shoulder 66which connects the cylindrical bores 40 and 38. A conduit 67communicates with the chamber 65 and also with the conduit .51,and-interposed in the conduit 67 is a hand valve 68, by means of whichthe supply of fluid under pressure 1 to'the. chamber 65 may becontrolled. A small orifice 65' is formed in the sleeve 46 to perm t arestricted escape of fluid from'the chamber 65. A pressure gauge 69communicates with the conduit 67 and indicates the pressure in thechamber 65. i A conduit 70, communicating with the conduit 51, isprovided for supplying fluid pressure from an auxiliary source instarting the prime mover.

The operation of the.,above described apparatus is as follows The partsare shown in the position of normal operation, in which the pressureofthe oil supplied to the impeller is sufficient to raise the piston 63against the spring 64, and in which the pressure developed by theimpeller is not sufiicient to raise the 42. In this position the pistonportion 60 is disposed-immediately above the port 47 and the pistonportion 44 is disposed below the port 52. Fluid pressure from theconduit 51 is therefore transmitted through the port 47,.

the'ports 48. the port 52, theconduit 34 and the orifice 27 to thethrottle valve operating mechanism 28 to retain the same in openposition.

Assume now that the prime mover exceeds a predetermined over-speed. .Theweights 58 are so adjusted that atsuch times the impeller r pressure onthe piston 42 overcomes the force of gravity of the weights and theeleinent'41,

and raises the piston 42. The pistonportion 6O thereupon covers theports 47 and cuts off further supply of fluid pressure to the throttlevalve operating mechanism. The piston portion 44 also moves upwardlyabove the port 52, placing the latter in communication with the drainport 54.

The oil in the throttle valve operating mechanism is free, therefore, toflow-through to effect a rapid closing of the throttle valve. 4

When the prime mover speed is restored to normal, the element 41 fallsby force of gravity to its normal position, in which position fluidunder pressure is conveyed to the throttle valve operating mechanism butescapes through the passage 33 without having any effect on the piston29 until the hand wheel 32' is operated to lower the stem-32. Theorifice 27 restricts the flow of fluid at this time to revent a loss ofpressure in the conduit 51.

en it is desired to test the automatic stop governor and the throttlevalve operating mechanism, at normal speed or any speed below thepredetermined overspeed, the hand valve 68 is slowly opened to admitfluid un der pressure from the conduit 51 to the chamber 65. Thepressure in said-chamber builds up and acts onthe piston portion 45until'the element 41 moves upwardly to trip the valve operatingmechanism. The pressure at which. the element 41 moves may be deter-.mined from the gauge 69, from which may be .In case of failure of oilpressure in the conduit 26, which supplies oil to the impeller 14,

the spring 64 forces the piston 63 and the valve member 59 downwardly.The piston 125. Thelow pressure trip operates as follows:

60., befoie, covers the ports 47 and cuts ofi the supply-of fluidpressure, .and the piston.

portion 61 moves below the ports 49, thereby placing the ports 52 incommunication with the drain conduit 35 through the ports 48, 49 and 54.The pressure in the cylinder 30 is released, as in the case ofoverspeed, and the throttle valve operating mechanism is tripped toclose the throttle valve.

Upon restoration of the minimum oil pressure in the conduit 26, thepiston 63 and the valve member 59 are moved upwardly to normal positionand a restricted flow of oil is again supplied to the throttle valveoperating mechanism. The stem 32 may then belowered and raised to againopen the throttle valve.

From the above description, it will be apparent that. I have provided anautomatic stop overspeed governor, which may be set without stopping theprime mover, by adding to or removing from the weights 58 on the disc57. It will also be noted that the governor automatically resets itself,except that when testing it is necessary to close the valve 68.

An advantage of my novel governor is that it may be placed at anydesired location, since it is hydraulically connected'to the apparatuswith which it cooperates.

A further advantage is that the force opposing the governing forceremains constant,-

and does not increase as in the case of spring force. Hence, when thepredetermined overspeed is exceeded and theelement 41 begins to move, itcontinues to do so without further increase in speed.

The low pressure trip of my automatic stop governor provides a specialprotection for the fluid pressure governor, which increases the fluidadmission with decrease in fluid pressure. In case of failure orabnormal drop in pressure of fluid sup-plied to the impeller, thepressure supplied to the governor would be correspondingly decreased andadmit an excessive amount of motive fluid. The low pressure trip guardsagainst such a possibility by closing the throttleivalve.

VVhile- I have shown niy invention in but one form, it will be obviousto those skilled in the art that it is not so limited, but issusceptible of various changes and modifications Without departing fromthe spirit thereof, and I desire, therefore, that only such limitationsshall be placed thereupon as are imposed by the prior art or as arespecifically set "forth in the appended claims.

What I claim is:

1. The combinationewith a prime mover and a throttle valve therefor, ofmechanism for operating said throttle valve, means pro viding a fluidpressure varying as a function pressure and adapted to control saidvalve operating mechanism to close the throttle valve upon apredetermined pressure, means for applying fluid pressure to anadditional area of surface of said element to effect movement thereof ata pressure on the first-memtioned area of less than the predeterminedpressure, and means for indicating the pressure on said additional area.

2. The combination with a prime mover and a throttle valve therefor, ofmeans for operating the throttle valve, means providing a fluidpressurevarying with the speed of the prime mover, an automatic stopgovernor responsive to saidfiuid pressure and adapted to control thethrottle valve operating means to efi'ect complete closing thereof,means for adjusting said governor to operate at a predeterminedpressure, and means independent of said adjusting means forefiectingoperation of said governor at a pressure less than the predeterminedpressure when testing the governor;

3. The combination with a prime mover having a throttle valve and agovernor valve controlling the admission of fluid thereto, of meansproviding a fluid pressure varying as a function of the speed of theprime mover, means providing a supply of fluid to said means, a governorresponsive to said pressure for regulating the governor valve, and meansresponsive to said supply for effecting complete closing of saidthrottle valve.

4. The combination with a prime mover having a throttle valve and agovernor valve controlling the admission of fluid thereto, of meansproviding a fluid pressure varying as a function of the speed of theprime mover, means providing a suppl of fiuid to said means, a governorresponsive to said pressure for regulating the governor valve, and meansresponsive to the pressure of the fluid su plied and for effectingcomplete closing of t e throttle valve.

5. The combination with a prime mover having a throttle valve and agovernor valve controlling the admission of fluid thereto, of meansproviding a fluid pressure varying as a function of the speed of theprime mover, means providing a supply of fluid to said means, agovernor. responsive to said pressure for regulating the governor valve,and means for eiieoting complete closing of the throttle valve uponfailure of said supply.

In testimony whereof, I have hereunto subscribed my name this 27th dayof July, 1928.

FRANK A. MEYER.

cumrlcm or common.

Patent'No. 1,816,020. Granted July H31, t0

. It is hereby certified that error sppears' in the printedspecification or the above" numbered patent requiring correction asfollows: Page 3, line 119. insert the following as claim 6 r 7 6. Thecombination with a prime mover and a throttle valve therefor, ofmechanism for operating said throttle valve, means providing a-fluidpressure varying as a function .of the speed of'theprime mover, anautomatic stop governor including an element having an area of surfacesuhjected to said flluiftlipre' eiand adapted to control said valveoperating mechanism tgeloae ithe throttle valve upon a predeterminedpressure, aad meansifbr appl'yjing fluid pressure to an additional areaof surface of ssid-elemeptftoeffectmovement thereof at a pressure on thefirst-mentioned amal ofiilea than the predeterminedv pressure.

and that the said Letters Patentshouldi be read with this correctiontherein'that the same may conform to the record.v Pf the case in thePatent 0ffiee.

sealed this 6th' as; j-joember. A. 1 1931.

MLJ. Moore,

(Seal) Aetinz Commissioner of Patents.

